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Autres articles (63)
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Les vidéos
21 avril 2011, parComme les documents de type "audio", Mediaspip affiche dans la mesure du possible les vidéos grâce à la balise html5 .
Un des inconvénients de cette balise est qu’elle n’est pas reconnue correctement par certains navigateurs (Internet Explorer pour ne pas le nommer) et que chaque navigateur ne gère en natif que certains formats de vidéos.
Son avantage principal quant à lui est de bénéficier de la prise en charge native de vidéos dans les navigateur et donc de se passer de l’utilisation de Flash et (...) -
(Dés)Activation de fonctionnalités (plugins)
18 février 2011, parPour gérer l’ajout et la suppression de fonctionnalités supplémentaires (ou plugins), MediaSPIP utilise à partir de la version 0.2 SVP.
SVP permet l’activation facile de plugins depuis l’espace de configuration de MediaSPIP.
Pour y accéder, il suffit de se rendre dans l’espace de configuration puis de se rendre sur la page "Gestion des plugins".
MediaSPIP est fourni par défaut avec l’ensemble des plugins dits "compatibles", ils ont été testés et intégrés afin de fonctionner parfaitement avec chaque (...) -
Activation de l’inscription des visiteurs
12 avril 2011, parIl est également possible d’activer l’inscription des visiteurs ce qui permettra à tout un chacun d’ouvrir soit même un compte sur le canal en question dans le cadre de projets ouverts par exemple.
Pour ce faire, il suffit d’aller dans l’espace de configuration du site en choisissant le sous menus "Gestion des utilisateurs". Le premier formulaire visible correspond à cette fonctionnalité.
Par défaut, MediaSPIP a créé lors de son initialisation un élément de menu dans le menu du haut de la page menant (...)
Sur d’autres sites (11102)
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FFmpeg, RTSP and Python : how to control it ?
3 juin 2016, par Grigory E.We can put the RTSP stream into mp4 container this way :
ffmpeg -hide_banner _RTSP-STREAM_ -c copy -map 0 -f segment -segment_time SEGTIME -segment_atclocktime 1 -segment_format mp4-strftime 1 PATH/%Y-%m-%d_%H-%M-%S.mp4"
The question is how to wrap it in Python and how to handle SOME errors ?
For example, some streams are buggy, so we should ignoreInvalid UE golomb with ffmpeg
But we should alert if the RTSP steram is down. And restart the FFmpeg....
P.S. I don’t think FFmepg is the best choice, but I don’t know anything else.
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YUV decoded by FFMPEG that draw with opengl is not clear
3 juin 2016, par S.JinI’m writing a movie player that use FFMPEG and OpenGL ES. Movie can be decoded succeessfully, but when I use AVFrame as texture to draw in my screen, I found it was so fuzzy. I don’t know where wrong in my code. If I change the AVFrame from YUV to RGB image, it will be clear.
Does any one know why use YUV as texture to draw will be not clear ?My render code :
#import "SJGLView.h"
#import <glkit></glkit>GLKit.h>
#import "SJDecoder.h"
#include "libavutil/pixfmt.h"
// MARK: - C Function
static void sj_logShaderError(GLuint shader) {
GLint info_len = 0;
glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &info_len);
if (info_len == 0) NSLog(@"Empty info");
else {
GLchar *log = (GLchar *)malloc(info_len);
glGetShaderInfoLog(shader, info_len, &info_len, log);
NSLog(@"Shader compile log: %s", log);
}
}
static void sj_logProgramError(GLuint program) {
int info_length;
glGetProgramiv(program, GL_INFO_LOG_LENGTH, &info_length);
if (info_length) {
GLchar *log = (GLchar *)malloc(info_length);
glGetProgramInfoLog(program, info_length, &info_length, log);
NSLog(@"Program link log: %s", log);
}
}
GLuint sj_loadShader(GLenum shader_type, const char* shader_source) {
GLuint shader = glCreateShader(shader_type);
glShaderSource(shader, 1, &shader_source, NULL);
glCompileShader(shader);
GLint compile_status = 0;
glGetShaderiv(shader, GL_COMPILE_STATUS, &compile_status);
if (!compile_status) goto fail;
return shader;
fail:
if (shader) {
sj_logShaderError(shader);
glDeleteShader(shader);
}
return 0;
}
void loadOrtho(float *matrix, float left, float right, float bottom, float top, float near, float far) {
float r_l = right - left;
float t_b = top - bottom;
float f_n = far - near;
float tx = (right + left)/(right - left);
float ty = (top + bottom)/(top - bottom);
float tz = (far + near)/(far - near);
matrix[0] = 2.0f / r_l;
matrix[1] = 0.0f;
matrix[2] = 0.0f;
matrix[3] = 0.0f;
matrix[4] = 0.0f;
matrix[5] = 2.0f / t_b;
matrix[6] = 0.0f;
matrix[7] = 0.0f;
matrix[8] = 0.0f;
matrix[9] = 0.0f;
matrix[10] = -2.0f / f_n;
matrix[11] = 0.0f;
matrix[12] = tx;
matrix[13] = ty;
matrix[14] = tz;
matrix[15] = 1.0f;
}
// BT.709, standard for HDTV
static const GLfloat g_bt709[] = {
1.164, 1.164, 1.164,
0.0, -0.213, 2.112,
1.793, -0.533, 0.0,
};
const GLfloat *getColorMatrix_bt709() {
return g_bt709;
}
enum {
ATTRIBUTE_VERTEX,
ATTRIBUTE_TEXCOORD,
};
@implementation SJGLView {
EAGLContext *_context;
GLuint _framebuffer;
GLuint _renderbuffer;
GLint _backingWidth;
GLint _backingHeight;
GLfloat _vertices[8];
GLuint _program;
GLuint _av4Position;
GLuint _av2Texcoord;
GLuint _um4Mvp;
GLfloat _texcoords[8];
GLuint _us2Sampler[3];
GLuint _um3ColorConversion;
GLuint _textures[3];
SJDecoder *_decoder;
}
+ (Class)layerClass {
return [CAEAGLLayer class];
}
- (instancetype)initWithFrame:(CGRect)frame decoder:(SJDecoder *)decoder {
self = [super initWithFrame:frame];
if (self) {
_decoder = decoder;
[self setupGL];
}
return self;
}
- (void)layoutSubviews {
glBindRenderbuffer(GL_RENDERBUFFER, _renderbuffer);
[_context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer*)self.layer];
glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_WIDTH, &_backingWidth);
glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_HEIGHT, &_backingHeight);
[self updateVertices];
[self render: nil];
}
- (void)setContentMode:(UIViewContentMode)contentMode
{
[super setContentMode:contentMode];
[self updateVertices];
[self render:nil];
}
- (void)setupGL {
_context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
NSAssert(_context != nil, @"Failed to init EAGLContext");
CAEAGLLayer *eaglLayer= (CAEAGLLayer *)self.layer;
eaglLayer.opaque = YES;
eaglLayer.drawableProperties = @{
kEAGLDrawablePropertyRetainedBacking: [NSNumber numberWithBool:YES],
kEAGLDrawablePropertyColorFormat: kEAGLColorFormatRGBA8
};
[EAGLContext setCurrentContext:_context];
if ([self setupEAGLContext]) {
NSLog(@"Success to setup EAGLContext");
if ([self loadShaders]) {
NSLog(@"Success to load shader");
_us2Sampler[0] = glGetUniformLocation(_program, "us2_SamplerX");
_us2Sampler[1] = glGetUniformLocation(_program, "us2_SamplerY");
_us2Sampler[2] = glGetUniformLocation(_program, "us2_SamplerZ");
_um3ColorConversion = glGetUniformLocation(_program, "um3_ColorConversion");
}
}
}
- (BOOL)setupEAGLContext {
glGenFramebuffers(1, &_framebuffer);
glGenRenderbuffers(1, &_renderbuffer);
glBindFramebuffer(GL_FRAMEBUFFER, _framebuffer);
glBindRenderbuffer(GL_RENDERBUFFER, _renderbuffer);
[_context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer *)self.layer];
glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_WIDTH, &_backingWidth);
glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_HEIGHT, &_backingHeight);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, _renderbuffer);
GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
if (status != GL_FRAMEBUFFER_COMPLETE) {
NSLog(@"Failed to make complete framebuffer object: %x", status);
return NO;
}
GLenum glError = glGetError();
if (glError != GL_NO_ERROR) {
NSLog(@"Failed to setup EAGLContext: %x", glError);
return NO;
}
return YES;
}
- (BOOL)loadShaders {
NSString *vertexPath = [[NSBundle mainBundle] pathForResource:@"vertex" ofType:@"vsh"];
const char *vertexString = [[NSString stringWithContentsOfFile:vertexPath encoding:NSUTF8StringEncoding error:nil] UTF8String];
NSString *fragmentPath = _decoder.format == SJVideoFrameFormatYUV ? [[NSBundle mainBundle] pathForResource:@"yuv420p" ofType:@"fsh"] :
[[NSBundle mainBundle] pathForResource:@"rgb" ofType:@"fsh"];
const char *fragmentString = [[NSString stringWithContentsOfFile:fragmentPath encoding:NSUTF8StringEncoding error:nil] UTF8String];
GLuint vertexShader = sj_loadShader(GL_VERTEX_SHADER, vertexString);
GLuint fragmentShader = sj_loadShader(GL_FRAGMENT_SHADER, fragmentString);
_program = glCreateProgram();
glAttachShader(_program, vertexShader);
glAttachShader(_program, fragmentShader);
glLinkProgram(_program);
GLint link_status = GL_FALSE;
glGetProgramiv(_program, GL_LINK_STATUS, &link_status);
if(!link_status) goto fail;
_av4Position = glGetAttribLocation(_program, "av4_Position");
_av2Texcoord = glGetAttribLocation(_program, "av2_Texcoord");
_um4Mvp = glGetUniformLocation(_program, "um4_ModelViewProjection");
return YES;
fail:
sj_logProgramError(_program);
glDeleteShader(vertexShader);
glDeleteShader(fragmentShader);
glDeleteProgram(_program);
return NO;
}
- (void)useRenderer {
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glUseProgram(_program);
if (0 == _textures[0]) glGenTextures(3, _textures);
for (int i = 0; i < 3; i++) {
glActiveTexture(GL_TEXTURE0 + i);
glBindTexture(GL_TEXTURE_2D, _textures[i]);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glUniform1i(_us2Sampler[i], i);
}
glUniformMatrix3fv(_um3ColorConversion, 1, GL_FALSE, getColorMatrix_bt709());
}
- (void)uploadTexture:(SJVideoFrame *)frame {
if (frame.format == SJVideoFrameFormatYUV) {
SJVideoYUVFrame *yuvFrame = (SJVideoYUVFrame *)frame;
const GLubyte *pixel[3] = { yuvFrame.luma.bytes, yuvFrame.chromaB.bytes, yuvFrame.chromaR.bytes };
const GLsizei widths[3] = { yuvFrame.width, yuvFrame.width/2, yuvFrame.width/2 };
const GLsizei heights[3] = { yuvFrame.height, yuvFrame.height/2, yuvFrame.height/2 };
for (int i = 0; i < 3; i++) {
glBindTexture(GL_TEXTURE_2D, _textures[i]);
glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, widths[i], heights[i], 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, pixel[i]);
}
}
}
- (void)render:(SJVideoFrame *)frame {
[EAGLContext setCurrentContext:_context];
glUseProgram(_program);
[self useRenderer];
GLfloat modelviewProj[16];
loadOrtho(modelviewProj, -1.0f, 1.0f, -1.0f, 1.0f, -1.0f, 1.0f);
glUniformMatrix4fv(_um4Mvp, 1, GL_FALSE, modelviewProj);
[self updateVertices];
[self updateTexcoords];
glBindFramebuffer(GL_FRAMEBUFFER, _framebuffer);
glViewport(0, 0, _backingWidth, _backingHeight);
[self uploadTexture:frame];
glClear(GL_COLOR_BUFFER_BIT);
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
glBindRenderbuffer(GL_RENDERBUFFER, _renderbuffer);
[_context presentRenderbuffer:GL_RENDERBUFFER];
}
- (void)updateVertices {
[self resetVertices];
BOOL fit = (self.contentMode == UIViewContentModeScaleAspectFit);
float width = _decoder.frameWidth;
float height = _decoder.frameHeight;
const float dW = (float)_backingWidth / width;
const float dH = (float)_backingHeight / height;
float dd = fit ? MIN(dH, dW) : MAX(dH, dW);
float nW = (width * dd / (float)_backingWidth);
float nH = (height * dd / (float)_backingHeight);
_vertices[0] = -nW;
_vertices[1] = -nH;
_vertices[2] = nW;
_vertices[3] = -nH;
_vertices[4] = -nW;
_vertices[5] = nH;
_vertices[6] = nW;
_vertices[7] = nH;
glVertexAttribPointer(_av4Position, 2, GL_FLOAT, GL_FALSE, 0, _vertices);
glEnableVertexAttribArray(_av4Position);
}
- (void)resetVertices {
_vertices[0] = -1.0f;
_vertices[1] = -1.0f;
_vertices[2] = 1.0f;
_vertices[3] = -1.0f;
_vertices[4] = -1.0f;
_vertices[5] = 1.0f;
_vertices[6] = 1.0f;
_vertices[7] = 1.0f;
}
- (void)updateTexcoords {
[self resetTexcoords];
glVertexAttribPointer(_av2Texcoord, 2, GL_FLOAT, GL_FALSE, 0, _texcoords);
glEnableVertexAttribArray(_av2Texcoord);
}
- (void)resetTexcoords {
_texcoords[0] = 0.0f;
_texcoords[1] = 1.0f;
_texcoords[2] = 1.0f;
_texcoords[3] = 1.0f;
_texcoords[4] = 0.0f;
_texcoords[5] = 0.0f;
_texcoords[6] = 1.0f;
_texcoords[7] = 0.0f;
}.fsh :
precision highp float;
varying highp vec2 vv2_Texcoord;
uniform mat3 um3_ColorConversion;
uniform lowp sampler2D us2_SamplerX;
uniform lowp sampler2D us2_SamplerY;
uniform lowp sampler2D us2_SamplerZ;
void main() {
mediump vec3 yuv;
lowp vec3 rgb;
yuv.x = (texture2D(us2_SamplerX, vv2_Texcoord).r - (16.0/255.0));
yuv.y = (texture2D(us2_SamplerY, vv2_Texcoord).r - 0.5);
yuv.z = (texture2D(us2_SamplerZ, vv2_Texcoord).r - 0.5);
rgb = um3_ColorConversion * yuva;
gl_FragColor = vec4(rgb, 1.0);
}.vsh file :
precision highp float;
varying highp vec2 vv2_Texcoord;
uniform lowp sampler2D us2_SamplerX;
void main() {
gl_FragColor = vec4(texture2D(us2_SamplerX, vv2_Texcoord).rgb, 1)
}Result image :
resultThe rgb image :
RGB image -
avfilter/vf_waveform : draw graticule for color filter too
7 mars 2016, par Paul B Mahol